2003 Freeflo, no high speed on pump

I think the model is a TLX. (Octagonal) Balboa control system. 115v (dual voltage model, powered by 115v). The pump is a 2 speed AquaFlo XP. The low speed works fine. When you select high speed there is a hum, higher current draw (the spa light dims slightly--I did not check with an amp meter), and the motor does not spin faster.

Thinking this was most likely a motor problem I took the motor to a local electric motor shop. They checked it out and said the pump/motor are fine. The cleaned up the switch inside while they had it, but proclaimed the motor is good.

So, now I get to troubleshoot the control board. I suspect a relay may be sticking, or something. My "day job" is in electronics, I have been a technician/engineer since the late 1970s so there may be some hope I can fix the board, not sure.

Any help and advice on this symptom would be greatly appreciated. Thanks!

You need to see if the circuit board is trying to send voltage to low speed and high speed at same time. There should be a wiring diagram on load box doors showing the pump relays. Also, verify your incoming power to spa which you probably already have done.

Thanks Mary! Great tip. Yes, incoming voltage is fine. Also, everything works except the high speed on the pump. I suspect if both voltages were being sent at the same time the most likely cause would be a relay hanging up or sticking (or contacts welded themselves closed) which should be pretty obvious visually. I haven't even looked at the board. I went immediately for the motor, thinking startup cap or internal switch. Now that the motor shop has given the motor a clean bill of health I need to look for the real cause. I still have to pick the pump/motor up from the shop, but hope to get back to troubleshooting this very soon--we want our spa working again!

I still have to go pickup the motor. Some additional info. I inspected the control circuit board. It is a Balboa Lite Leader 54115. All of the relays look mechanically fine and the contacts look fine (and have no contact resistance when checked with an ohm meter).

I'm not quite sure how to measure the motor voltage outputs without putting the spa back together and filling with water. I'm sure there is a way to "fool" the various sensors to the board (it seems pretty simple), but service information on that board is not forthcoming from a google search.

The board appears to be available, but I don't want to replace it unless I know for sure it is bad. Worst case, I suppose, is I go ahead an fill the tub to test. The relays are open so I can watch the contacts pull in too.

Is there a way to test the board for motor control output without filling the tub? What is the control looking for to allow the motor outputs to turn on? (I'm assuming pressure and/or flow switch inputs?)

You don't really want to run the pump dry. You can disconnect the heater and wires leading to pump and then turn on jet button and test voltage coming from circuit board relays. This won't allow anything to come on but should still allow voltage going to pump motor.